The objective of this proposal is to improve the diagnosis, treatment and outcome of children with cancer through participation in protocols designed by the Childrens Cancer Groups (CCG). We plan to enter eligible patients on CCG protocols, participate in the development and execution of these protocols, supply materials for and execute biological studies of cancer through CCG, serve as a referral center for other CCG institutions which lack facilities for bone marrow transplantation or for phase I chemotherapy and to perform independent studies which may serve as the basis for future CCG studies. The Children's Hospital Medical Center (CHMC) is the major pediatric medical center in the greater Cincinnati area with a population of 2 million people. CHMC is the only hospital wit pediatric inpatient capabilities within a 50 to 75 mile radius of Cincinnati and is one of the three largest pediatric medical centers, within the United States. There are four medical centers affiliate with CHMC: the University of Kentucky, Lexington, KY; Children's Hospital of Akron, Akron, OH; the Penn State University Children's Hospital, Hershey, PA; and Scottish Rite Children's Hospital, Atlanta, GA. Combined, they served population areas of another 8 to 10 million people. Together, we have become the second largest contributor of patients to CCG studies. Personnel from CHMC and its affiliates have made many contributions to the administration of the CCG and to its scientific studies. Highlights of this participation include personnel serving as Associate Chair for Leukemia Studies, member of the Executive Committee of the CCG, Chair of the AML strategy Group, Vice Chair of numerous strategy groups and leading study committees. CHMC provides the CCG with one of its oldest and largest pediatric Bone Marrow Transplantation units. This unit has expanded from 5 to 8 beds in the past five years and will be expanded to 12 beds when our new clinical tower is completed in January of 1994. This unit has been particularly active in transplantation of patients with neuroblastoma, acute myeloid leukemia and brain tumors. CHMC also became one of the relatively few phase I institutions during the past five years adding to the CCG's capability to perform these unique and difficult studies. We have also been a leading contributor to cancer biologic studies, the second leading contributor to the Human Tumor Tissue Network and have served as a center for pediatric tumor xenografts which allow completion of additional studies of the biology of these tumors.